This talk from GDC 2015 is an in-depth analysis of camera implementation techniques for 2D side-scrollers. This is something that seems trivial at first; however, there is a wealth of possibilities in framing, thresholds, acceleration and deceleration curves, motion prediction and other techniques that can make your camera feel more natural, responsive and fluid. In 2D, where we don't typically think about the camera as consciously as we do in 3D, this attention to detail can have a dramatic impact on how the player experiences the game without them even realizing it.